﻿/* Copyright 2010-2012 10gen Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.Text.RegularExpressions;

using MongoDB.Bson.IO;

namespace MongoDB.Bson.Serialization.Serializers
{
    /// <summary>
    /// Represents a serializer for IPEndPoints.
    /// </summary>
    public class IPEndPointSerializer : BsonBaseSerializer
    {
        // private static fields
        private static IPEndPointSerializer __instance = new IPEndPointSerializer();

        // constructors
        /// <summary>
        /// Initializes a new instance of the IPEndPointSerializer class.
        /// </summary>
        public IPEndPointSerializer()
        {
        }

        // public static properties
        /// <summary>
        /// Gets an instance of the IPEndPointSerializer class.
        /// </summary>
        public static IPEndPointSerializer Instance
        {
            get { return __instance; }
        }

        // public methods
        /// <summary>
        /// Deserializes an object from a BsonReader.
        /// </summary>
        /// <param name="bsonReader">The BsonReader.</param>
        /// <param name="nominalType">The nominal type of the object.</param>
        /// <param name="actualType">The actual type of the object.</param>
        /// <param name="options">The serialization options.</param>
        /// <returns>An object.</returns>
        public override object Deserialize(
            BsonReader bsonReader,
            Type nominalType,
            Type actualType,
            IBsonSerializationOptions options)
        {
            VerifyTypes(nominalType, actualType, typeof(IPEndPoint));

            BsonType bsonType = bsonReader.GetCurrentBsonType();
            string message;
            switch (bsonType)
            {
                case BsonType.Null:
                    bsonReader.ReadNull();
                    return null;
                case BsonType.String:
                    var stringValue = bsonReader.ReadString();
                    var match = Regex.Match(stringValue, @"^(?<address>(.+|\[.*\]))\:(?<port>\d+)$");
                    if (match.Success)
                    {
                        IPAddress address;
                        if (IPAddress.TryParse(match.Groups["address"].Value, out address))
                        {
                            int port;
                            if (int.TryParse(match.Groups["port"].Value, out port))
                            {
                                return new IPEndPoint(address, port);
                            }
                        }
                    }
                    message = string.Format("Invalid IPEndPoint value '{0}'.", stringValue);
                    throw new FileFormatException(message);
                default:
                    message = string.Format("Cannot deserialize IPEndPoint from BsonType {0}.", bsonType);
                    throw new FileFormatException(message);
            }
        }

        /// <summary>
        /// Serializes an object to a BsonWriter.
        /// </summary>
        /// <param name="bsonWriter">The BsonWriter.</param>
        /// <param name="nominalType">The nominal type.</param>
        /// <param name="value">The object.</param>
        /// <param name="options">The serialization options.</param>
        public override void Serialize(
            BsonWriter bsonWriter,
            Type nominalType,
            object value,
            IBsonSerializationOptions options)
        {
            if (value == null)
            {
                bsonWriter.WriteNull();
            }
            else
            {
                var endPoint = (IPEndPoint)value;
                string stringValue;
                if (endPoint.AddressFamily == AddressFamily.InterNetwork)
                {
                    stringValue = string.Format("{0}:{1}", endPoint.Address, endPoint.Port); // IPv4
                }
                else
                {
                    stringValue = string.Format("[{0}]:{1}", endPoint.Address, endPoint.Port); // IPv6
                }
                bsonWriter.WriteString(stringValue);
            }
        }
    }
}
